I have the same problem with batteries dying – I have taken to removing them after use. I also found that the batteries that supposedly died still worked when I put them back into the units. I have not tried any other batteries except the ones that came with the units. Perhaps the original equipment batteries are poor quality. The units still use some current when shut off otherwise the axis settings would be lost when you shut down the machine when the wife calls you for dinner.
I have considered modifying the units to be run off of a wall wart but have not had the courage to take a soldering iron to the units. I assume that a 6 volt transformer would do the trick. Anyone tried this?
AJ
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